成分及性能连续变化梯度涂层的半导体激光制备

Composition and Properties Continuously Changed Gradient Coating Fabricated by High Power Diode Laser

为了获得成分及性能连续变化的梯度涂层,采用2.5kW半导体激光器和四路联动送粉系统,利用旁轴送粉方式,通过成形过程中实时改变Ni25/Ni60双组分自熔合金粉末及AlSi12/Fe62双金属自熔合金粉末的组分配比,在45#钢棒状基体上分别制备了宽度为9mm的粉末组分连续变化的螺旋状梯度涂层。对涂层试样进行能量色散谱(EDS)、显微组织及显微硬度测试。结果表明,沿涂层制备方向,Ni25/Ni60梯度涂层中Cr元素含量和显微硬度连续降低;AlSi12/Fe62梯度涂层中Fe、Cr和Al等元素含量分别沿制备方向连续变化;两种涂层各自的显微组织呈明显变化。

To obtain gradient coating with changed components and properties, the gradient coating comprised of two-kind metal powders （Ni25/Ni60 and A1Si12/Fe62） is fabricated with paraxonic synchronism powder feeding mode, 2.5 kW high power diode laser and 4 channels powder system. The 9-ram width spiral gradient coatings on 45 # steel stick are achieved. Meanwhile, energy dispersive spectroscopy （EDS）, microstructure and micro-hardness of coating are studied. The experimental results show that along the forming direction, the content of element Cr and the micro-hardness decrease continuously in Ni25/Ni60 gradient coating; the contents of elements Fe, Cr and A1 change continuously in AISi12/Fe62 gradient coating; the microstructures in both coatings change obviously.